Pyrite with Galena (RARE from Tsumeb)

Item Description

Of the hundreds of species from Tsumeb, there aren't a lot of well-crystallized sulfides. This is due in part to the fact that most of the ore minerals were altered and became secondary ore species, but the mining that took place beyond the oxidized zone did produce some sulfides like Pyrite. Although Pyrite is a very common sulfide species, it's notably rare from Tsumeb. Obviously this locality was loaded with copper, lead, zinc and many other rare elements like germanium and cadmium, but I have been told that there wasn't a lot of iron at Tsumeb, which explains why you don't see much in the way of Pyrite. This particular specimen is a very impressive crystallized Pyrite for the locality featuring a full coverage of sharp, well-formed, metallic, striated pyritohedral crystals measuring up to 2.0 cm across associated with dark grey Galena on the underside. The Pyrites have a coating on the surface and I cannot say for certain if the coating is more Galena or possibly something like Chalcocite or Tennantite. If you look closely with a loupe, you can see tiny areas of metallic golden Pyrite that are poking through the coating, so this isn't a replacement or a pseudomorph. The piece is in great shape, and when you look closely, you can really appreciate the fine crystallization, amplified by the stark striations of the crystals. A really impressive and desirable piece from this most prolific of localities.
From the collection of William ("Bill") (1927-2006) and Anne (1928-2021) Cook of Cleveland, Ohio (#14028) with a label from the collection of Dr. Günther Grundman (#836). This husband and wife duo were actively involved in the mineral world for many decades. Bill was a PhD geologist, and Anne was a mathematician, and they both were very serious mineral collectors. Bill served for many years as adjunct curator of mineralogy at the Cleveland Museum of Natural History, and Anne was inducted into the Micromounters' Hall of Fame on October 12, 2019. Both Bill and Anne, at various times, served as president both of the Mineralogical Society of Cleveland and of the Micromineral Society of the Cleveland Museum of Natural History, and Anne was inducted into the mi The rare barium lithium beryllium phosphate Wilancookite was named in their honor in 2015.